The Platinum Channel: Higgs Decays to as many as 8 Leptons

Abstract

We propose a search for Higgs decays with as many as eight leptons in the final state. This signal can arise in a simple model with a hidden vector ($A_d$) that gets mass via a hidden scalar ($h_d$) vacuum expectation value. The 125 GeV Higgs can then decay $H\to h_d{h}_d\to 4A_d\to 8f$, where $f$ are Standard Model fermions. We recast current searches and show that a branching ratio of $H\to h_d{h}_d$ as large as 10% is allowed. We also describe a dedicated search that could place bounds on BR($H\to h_d{h}_d$) as low as $10^{-5}$ using only 36 fb${}^{-1}$ of data, with significant improvements coming from greater integrated luminosity.

Comments: 7 pages, 2 figures. v2: References added. v3: A more detailed background study; approximate version published in PRL